Mohamed al Fayed arrives at the High Court in London for a preliminary hearing into the deaths of Princess Diana and his son Dodi Fayed on Monday. The hearing, at London's High Court, was originally intended to decide the scope of the inquest, determine which witnesses would be called, and demonstrate the virtual reality scene which is to be used during the proceedings. But a decision by a panel of judges, released last week, could affect the proceedings.

London ? A British coroner demanded Monday that those who believe Princess Diana and her boyfriend Dodi Fayed were murdered should show her the evidence and said she may delay an inquest into their deaths until October.

The long-awaited inquest also could hear testimony about Diana’s alleged fears for her life, the significance of a ring purchased by Fayed and whether the princess was pregnant, lawyers said during preliminary hearings at London’s High Court.

After originally declaring she would be extremely reluctant to delay the inquest’s start date of May 8, Baroness Elizabeth Butler-Sloss, a retired judge overseeing the proceedings, conceded the demands of lawyers and witnesses could lead to a postponement. The inquest could last as long as eight months.

Monday’s hearings were procedural, with arguments over everything from the suitability of the courtroom to the use of computer virtual reality in reconstructing the crash.

Butler-Sloss issued pointed instructions to lawyers for Mohamed al Fayed, Dodi’s father and the owner of Harrods department store, to provide evidence to back up his long-held claims that a conspiracy was responsible for the deaths.

In particular, al Fayed contends Prince Philip, husband of Queen Elizabeth II, was behind their deaths, and that the plot was carried out by British secret services. Philip has never commented on the allegations.

“There are a large number of serious allegations being made,” Butler-Sloss said. “At the moment, there is not a shred of evidence given to me about these allegations.

“Let me make it very clear – if there is no evidence supporting them, I shall not present them to the jury.”

Michael Mansfield, al Fayed’s lawyer, said “none of the claims are wild,” and indicated that his legal team needed access to documents and evidence collected by the Metropolitan Police during their three-year probe into the deaths.

That investigation, results of which were released in December – and which are disputed by al Fayed – concluded that Diana was not pregnant or about to marry Fayed, and that the crash was caused by chauffeur Henri Paul, who was drunk and speeding.

Mansfield also said Diana’s ex-husband, Prince Charles, and Prince Philip should be called to give evidence at the inquest as witnesses. He asked for a six-month delay to prepare for the inquest, citing the need to gather expert evidence and documentation – and noting that the pause would be “a pebble on the beach” in the context of a 10-year wait to open an inquest.

The request for a delay was backed by lawyers for the family of Paul, who suggested members of the French paparazzi – reluctant to cooperate with previous probes over fears they could be charged criminally – may be more willing to come forward when the statute of limitations in the case runs out on Aug. 31, 2007.

Diana’s sister, Lady Sarah McCorquodale, and Maj. Jamie Lowther-Pinkerton, private secretary to Princes William and Harry, were in court to represent Diana’s family. Al Fayed sat on the other side of the small courtroom.

Monday’s hearing was originally intended to decide the scope of the inquest, determine which witnesses would be called and demonstrate the virtual reality recreation of the crash scene which is to be used during the proceedings.

Butler-Sloss had originally decided to conduct the inquest without a jury. A three-judge panel overturned that decision after a challenge by al Fayed and ruled a jury should deliver the verdict.

“I have no intention of ever appealing the decision,” Butler-Sloss said.

Under British law, inquests are held when someone dies unexpectedly, violently or of unknown causes.

Diana, 36, and Fayed, 42, were killed along with chauffeur Paul when their Mercedes crashed in the Pont d’Alma tunnel on Aug. 31, 1997. The only survivor, bodyguard Trevor Rees – formerly known as Rees-Jones – was badly hurt.